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finlep [7]
2 years ago
14

The horn on a fire truck sounds at a pitch of 350 hz a. what is the perceived frequency when the fire truck is moving toward you

at 20m/s? b. What is the perceived frequency when the fire truck is moving away from you at 20m/s: assume the speed of sound in air is 343m/s.
​
Physics
1 answer:
solong [7]2 years ago
5 0

The perceived frequency when the fire truck is moving toward you and away from you will be 370 Hz and 329.59 Hz respectively.

<h3>What is the Doppler effect?</h3>

A sudden change in the frequency due to the distance between the objects and source is explained by the doppler effect.

As the source and observer travel toward each other, the frequency of sound, light, or other waves increases or decreases.

The perceived frequency when the fire truck is moving toward you;

\rm r' = (\frac{v+v_0}{v}) V \\\\ \rm r' = (\frac{343+20}{343}) 350 \\\\ r' =370.4  \  Hz

The perceived frequency when the fire truck is moving away from you;

\rm r' = (\frac{v-v_0}{v}) V \\\\ \rm r' = (\frac{343-20}{343}) 343 \\\\ r' =329.59  \  Hz

Hence, the perceived frequency when the fire truck in cases 1 and 2 will be 370 Hz and 329.59 Hz.

To learn more about the doppler effect refer to the link;

brainly.com/question/15318474

#SPJ1

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Explanation:

Given

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When the hand is h=2.5\ m above the ground

Using the equation of motion we can write

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An airplane propeller is 2.68 m in length (from tip to tip) and has a mass of 107 kg. When the airplane's engine is first starte
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